1. Field of the Invention
This invention relates generally to phonograph record players, and more particularly is directed to an improved phonograph record player control mechanism for effecting lead-in movement of a tone arm from an elevated rest position outside the perimeter of a turntable to a selected set-down position on a record supported by the turntable so as to commence a play operation, and for effecting a return movement of the tone arm to its rest position upon the termination of the play operation.
2. Description of the Prior Art
Phonograph record players are known, for example, as disclosed in U.S. Pat. Nos. 3,311,380 and 3,599,984, in which a control gear having a toothless gap in its periphery is disposed, during a play operation, with such toothless gap facing a drive gear rotatable with the turntable, and in which, at the completion of a play operation, for example, during the tracking by the stylus of a lead-out groove of a phonograph record, an electromagnet is energized to move a trip or clutch on the control gear to its operative position in which an abutment rotating with the drive gear acts against the trip for initiating rotation of the control gear by which the tone arm is returned to its rest position. However, the foregoing record player control mechanisms do not employ similar arrangements for effecting the automatic lead-in movement of the tone arm to a selected set down position on the record.
In addition to the foregoing, so-called automatic phonograph record players are known in which a control mechanism is provided for effecting automatic lead-in movement of a tone arm from its elevated rest position outside the perimeter of a turntable to a selected set-down position on a record supported by the turntable so as to commence a play operation, and for effecting an automatic return movement of the tone arm to its rest position upon the termination of the play operation. In such known control mechanism, for example, as disclosed in U.S. Pat. No. 3,438,635, a control gear with cam surfaces thereon for controlling the lateral swinging movements and the raising and lowering of the tone arm is provided with first and second toothless gaps in its peripheral teeth which respectively face toward a drive gear rotating with the turntable when the control gear is in stop and play positions thereof. In order to initiate turning of the control gear from its stop position, a manually operable control knob is actuated to displace a lever which thereby acts against an abutment on the control gear for angularly displacing the latter so as to engage its peripheral teeth with the drive gear, whereupon the latter turns the control gear to its play position at which the second toothless gap confronts the drive gear and a single clutch or trigger mechanism on the control gear is adjacent an abutment or striker rotating with the drive gear. During the turning of the control gear from its initial or stop position to the play position, the cam surfaces thereon are effective through link mechanisms to cause the lead-in movement of the tone arm to a selected set-down position on a record for commencing a play operation. At the completion of a play operation, a part of the link mechanism connected to the tone arm actuates the clutch or trigger mechanism for engaging the latter with the rotated striker in response to the positioning of the tone arm in correspondence to the engagement of the stylus with the lead-out or final portion of the record groove so as to again initiate turning of the control gear by the drive gear for returning the control gear to its initial or stop position and thereby effecting the return movement of the tone arm. In the event that it is desired to effect a reject operation, that is, to cause the return movement of the tone arm prior to the completion of a play operation, the previously mentioned control knob is again manually actuated for displacing the associated lever which, with the control gear in its play position, acts against the clutch or trigger mechanism for engaging the latter with the rotated striker and thereby initiating turning of the control gear from its play position to its stop position. It will be seen from the foregoing that the described control mechanism of the prior art employs a manually actuable, multi-part mechanical arrangement for initiating a lead-in or reject operation and a separate mechanical arrangement for initiating a normal return operation at the completion of the playing of a record. Such control mechanism is disadvantageous in that the multi-part mechanical arrangement for initiating the lead-in and reject operations is relatively costly to produce and assemble, and in that a relatively large force has to be manually applied to the control knob for initiating such operations. Furthermore, due to the multi-part character of the mechanical arrangement, an undesirable time delay occurs between the application of force to the control knob and the initiation of either the lead-in movement of the tone arm or the return movement of the tone ar in a reject operation.
Although it has also been proposed in the prior art to provide a record player control mechanism with a control gear having cams thereon for effecting the lead-in and return movements of the tone arm, and with two clutch or trigger mechanisms on the control gear which are respectively engaged for initiating the turning of the control gear during the lead-in and return operations, such existing control mechanism also employs manually actuated multi-part mechanical arrangements for effecting engagement of the clutch or trigger mechanisms. Therefore, a control mechanism of the last described type is also burdened by the above mentioned disadvantages of the control mechanism disclosed in U.S. Pat. No. 3,438,635.